be723a8d8c
Summary: MemTableInserter default constructs Post processing info std::map. However, on Windows with 2015 STL the default constructed map still dynamically allocates one node which shows up on a profiler and we loose ~40% throughput on fillrandom benchmark. Solution: declare a map as std::aligned storage and optionally construct. This addresses https://github.com/facebook/rocksdb/issues/1976 Before: ------------------------------------------------------------------- Initializing RocksDB Options from command-line flags DB path: [k:\data\BulkLoadRandom_10M_fillonly] fillrandom : 2.775 micros/op 360334 ops/sec; 280.4 MB/s Microseconds per write: Count: 10000000 Average: 2.7749 StdDev: 39.92 Min: 1 Median: 2.0826 Max: 26051 Percentiles: P50: 2.08 P75: 2.55 P99: 3.55 P99.9: 9.58 P99.99: 51.5**6 ------------------------------------------------------ After: Initializing RocksDB Options from command-line flags DB path: [k:\data\BulkLoadRandom_10M_fillon Closes https://github.com/facebook/rocksdb/pull/2011 Differential Revision: D4740823 Pulled By: siying fbshipit-source-id: 1daaa2c
RocksDB: A Persistent Key-Value Store for Flash and RAM Storage
RocksDB is developed and maintained by Facebook Database Engineering Team. It is built on earlier work on LevelDB by Sanjay Ghemawat (sanjay@google.com) and Jeff Dean (jeff@google.com)
This code is a library that forms the core building block for a fast key value server, especially suited for storing data on flash drives. It has a Log-Structured-Merge-Database (LSM) design with flexible tradeoffs between Write-Amplification-Factor (WAF), Read-Amplification-Factor (RAF) and Space-Amplification-Factor (SAF). It has multi-threaded compactions, making it specially suitable for storing multiple terabytes of data in a single database.
Start with example usage here: https://github.com/facebook/rocksdb/tree/master/examples
See the github wiki for more explanation.
The public interface is in include/. Callers should not include or
rely on the details of any other header files in this package. Those
internal APIs may be changed without warning.
Design discussions are conducted in https://www.facebook.com/groups/rocksdb.dev/